1. Field of the Invention
The present invention relates to a method of and a system for predicting the print colors of a print produced by a printing press.
2. Description of the Related Art
Prints are produced by, for example, generating original film plates in various colors including cyan (C), magenta (M), yellow (Y), and black (K), for example, producing PS plates (presensitized plates) from the original film plates by exposure and development, mounting the PS plates on a printing press such as a rotary press or the like, and adjusting printing conditions including the ink film thickness, the dampening water, the temperature, etc.
As described above, complex steps are involved in producing prints. In order to produce a print in desired colors, it has been customary prior to the production of the print to generate a proof sheet using a simple output device such as a monitor, a color printer, or the like, and adjust printing conditions in order for the proof sheet-to have the desired colors of the print to be produced.
Japanese Laid-Open Patent Publication No. 2006-128760, for example, discloses a method of generating color charts respectively with a printing press and a color printer, or the like, colorimetrically measuring the color charts, determining an ICC (International Color Consortium) profile representing the correspondence relationship between the halftone dot % of inks in the colors C, M, Y, K and the colorimetric values, and generating a proof sheet for prints using the ICC profile. The density of a solid image, i.e., an image with a halftone dot percent of 100%, is usually defined as a standard density by a user which may be a printing company or the like. Printing conditions including the film thickness of inks on printing presses are adjusted to achieve the standard density.
The standard density of prints may differ from user to user. If the standard density is to be changed, then it is necessary to print color charts again and produce an ICC profile once more. However, such a process is time-consuming because the color charts, each made up of a number of color patches, need to be printed and colorimetrically measured for the new standard density.